Process for recovery of cane-sugar.



A saving of sugar is effected, the recovery filtered either of sugar, and finally the exhausted or waste following .cane sugar isJdisposed of at little U, TERRITORY or HAWAII.

PROCESS FOR RECOVERY OF CANE-SUGAR.

No Drawing.

To all whom or may concern:

' Be it known that I, EUGENE ERLE BATTELLE, a citizen of the United States, residing at Wailuku, county. of Maui, Territory of Hawaii, have invented certain new and useful Improvements in Processes for Recovery of Caneugar; and I do hereby declare the to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertainsto make and use the samey invention relates to processes for the recovery of cane sugar, and particularly to a process for the manufacture of white sugars from juices, syrups, molasses and massecuites containing glucose, known as in- Vert sugar; and has for its objects, the elimination of glucose, the increasing of thepurities of all materials, the production of a white table or single grade of marketable raw sugar, and the extracting of a maximum amount of sugar with a minimum loss of the sugar contained in the initial material.

The invention consists in the novel process as hereinafter set forth and claimed.

My process can be carried out in existing sugar factories With economical results. The glucose is eliminated by addition of sufiicient oxid of alkaline earths, boiling and filtering, the solution being boiled previousto a treatment with acid, preferably carbonic or sulfurous acid, as hereinafter explained. By the elimination of the glucose, the purities of all materials are increased.

of which was heretofore prevented by the presence of large quantities of glucose in the molasses. The production of white refined or a single grade of raw sugar, made possible by my process, effects a saving in equipment, in'labor, and in the time required for manufacture, as the remelting, reboiling, redrying and rehandling of several grades of sugar are obviated.

In the ordinary process of manufacture of raw sugar, the cane juice is limed to neutrality, heated to or near the boiling point, by decantation or other means, the juice concentrated and boiled to grain, the latter operation being repeated until there is no longer a profitable recovery molasses still containing from 30% to 40% profit; All products from juice to exhausted Specification of Letters Patent. Application filed June 16, 1910.

or no Patented Nov. 12, 1912. Serial No. 567,191.

molasses being more or less rich in glucose, increases the number'of boilings (grades of sugar) and makes it impossible to recover more sugar from the above mentioned exhausted molasses.

In carrying out my improved'process, the raw juice is limed with quick lime, milk of me, saccharate of lime, or its equivalent of the alkalineearth group, to form 1% to 5% of the weight of the juice. It is then heated to or near theboiling point, either by pumping through a-heater, or by other means of attaining this end. N o definite amount of alkali can be specified as the percentage of glucose is variable, but suflicient alkalinity is maintained to destroy suflicient glucose, upon boiling the juice, so as to render the process as described commercially or economically operative; After boiling, the hot solution is run into a first carbonation tank,

where acid, preferably carbonic acid, is-

passed through it until the solution filters readily, when the acid is stopped, and the solution is filtered either by decantation or by mechanical means. In the former case the precipitate is filter pressed. The resulting filtered liquid is now sent to a second I carbonation tank, where the alkalinity is increased if desired, and carbonic or sulfurous acid passed through the liquid until the solution is allmost neutral to litmus paper. 7

In juices or sugar solutions containing a low percentage of glucose the single carbonation is sufficient, provided that the lime or its substitute in solution is completely, or nearly so, removed by continued carbonic application.

In producing white sugar or w1th a very impure juice of high glucose content Where an excessive amount of lime is required to destroy the glucose, it is advisable to introduce raw sugars from other factories into the juice prior to the addition of lime and carbonation. This latter method not only decreases the amount of lime and thereby the cost of'production but also inc reases the qualit y of the sugar. With impure'juices high in glucose and requiring a large amount of lime, it will be profitable to treat same by the Well known and generally used defecation process (adding only a suflicient amount of lime to coagulate albuminous matter after boiling, and filter by decantation) prior to the destruction of the glucose as above stated. This method saves I. other sugar house products) by anyof the 25. passed through white sugar.

- ing applies not only to in the amount of lime required. In any case 'the filteredsolution is now concentrated to svrun.

The invention 'so far as above disclosed the manufacture of raw sugar,but it may also be employed in connection with the refining processes now in use. Should the raw' sugar contain glucose, the rem'elt sugars, syrups, molasses or massecuites, may be treated by the above desc'ribed'process to decompose the invert sugar, the latter passing ofi' with the sludge or press-cake as a metalhcglu- 'cosate.

- After evaporating the solution (juices or the latter is devices nowin use to a syrup,

yieldboiled to grain in the vacuum pans,

- point a white refined article may be made or raw-sugars for refiners maybe produced.

from 70 to 75 purity.

-In case of the former,

In allsucceeding strikes or boilings,syrup or thick juice is used. as in the first case on in-smaller amounts, the first molasses belng;

boiled in .on'same at the finish of the strike;

to. lower the purity of the massecuite to.

No definite propor-. tions of syrup and molasses can be specified owing to the varied purities of either or both ofsame; but the object is to lower the purity of the massecuite by boiling the first or only molasses produced in on the syrup grain in such proportions as to yield a single ade of massecuite of from to 5 purity after .treatment in crystallizers from '12 to 60 hours and the crystals separated from molasses by centrifuga'ls, yieldinga sugar of 9 6-to 97 polarization and molasses of from 50 to 60 purity. The molasses from this or the molasses from the white, sugar, after a second boiling, is to be treated by the well known lime separation process as used in the beet sugar industry, making a further recovery of sugar that up to this time has been impossible owing to theglucose in sugarcane products which combine' in the cold with the lime and laterthereby decreasing the purity decompose,

the

of the sucrose solution produced from lime-sacchar'ate combination.

Where there are suifioient reducin sugars in the molasses to be treated by the-limeseparation process, to produce a low purity saccharate, such molasses to be refined.

in the thereby boiling heat,

should be treated mately the boiling point. while in anon-acidl ine-4,004

as juice, as hereinbefore explained, prior to said separation process. 7

As previously intimated, the most important characteristic of the present invention is that it provides for the removal of the glucose from the juice,syrup or other sugar .house solution or product which is initially treated, whereby a white sugar, of high obtained and likewise a high,

purity is purity-molasses [of which the latter, by reason of its freedom from glucose, is susceptible of. a further recovery of sucrose by the well-knownlime separationrocess as employed in' the beet sugar in ustry. These results are absolutely new in the art, so far as I am aware, and my improvements are also accompanied by thegreat advantage that the destruction (in large part) of the glucose'can be carried out quickly and economically.' In order to throw down the glucose the lime must obviously be added to the solution in excess and samples otthe solution must first be tested with different quantities of lime until the desired results are obtained. The application of thehigh temperature specified then causes the rapid formation of the precipitate, which is then removed together with the latter being first thrown down asa carbonate by the applicationofcarbonic acid as above described." Inasmuch as the solution is. maintained in a non-acid state, there is no further inversion of sugar at'any stage rocess.

My invention has numerous advantages over the ordinary carbonatation process as used for the recovery of cane sugar in some few instances, in that the large amount of lime, in connection with the high temperatures, eliminates the waxes, guns, pectine and most of the coloring matter, whereby a centrifugals with little .water to a white the xcess of lime,

is obtained. This juice can be color-free sugar such as it is impossible to I obtain with the present carbonatation process. p v 1 The term solution is used in the claims in a broad sense, as denoting a juice, syrup or other sugar house product. will be understood that while the wellknown lime separation .(Steftens) process, ascarried out inthe beet sugar industry, is preferable for the recovery of sucrose from thejpurlfied molasses, other lime treatments may be used with success I claim:

1. A process for the recovery of cane sugar, I

which comprises adding to a cane sugar .so

- lution an oxid-of alkaline earthin s'ufii'cient quantity to practically eliminate the gluapplication of approximately cose on the heating the solution to approxi- 115 Of course, it 4 state, treating the solution,with a suitable acid to remove the excess of lime, and then filtering; substantially as described.

2. A process for the recovery of cane sugar, which comprises the addition to a cane sugar solution of an oxid of alkaline earth, in suflicient quantity to destroy the greater part of the glucose on the application of approximately boiling heat, heating the solution to the aforesaid extent, until the glucose is thrown down as precipitate or decompose, and then passing carbonic acid through the solution; substantially as described. i

3. A process for the recovery of cane sugar, which comprises adding lime in excess to a cane sugar solution, then heating the solution to an approximately boiling temperature, while in a non-acid state, and fora sufiicient length of time to precipitate or destroy the greater part of the glucose, then removing the excess of lime, and finally filtering the solution; substantially as described.

4. A process for the recovery of cane sugar, which comprises the addition to a cane sugar solution of lime or its equivalent, in a proportion of from 1% to 5% of the weight of the solution, depending on the glucose content of the latter, then heating the solutionto approximately the boiling point while in a non-acid condition, until the glucose is thrown down as a lime-glucose or similar precipitate, then passing carbonic acid through the solution to remove the excess of lime, and finally filtering the solution; substantially as described. I

5. A process for the recovery of cane sugar, which comprises the elimination of the-glucose in the juice or other sugar house product by the addition of an excess of lime to the latter, and the application of approxi mately boiling heat, recovering crystallized sugar from the purified solution, and a r to grain and thereby molasses substantially freed from glucose, and then effecting a further recovery of sugar from the molasses by a lime separat1on process; substantially as described.

6. process for the recovery of cane sugar, which consists in the preliminary treatment of a cane sugar solution to eliminate'the greater part of the glucose, boiling the purified solution to grain and thereby recovering a white sugar and a molasses largely freed from glucose, and then efiecting a further recovery of sugar from the molasses by subjecting the latter to a lime separation treatment; substantially, as described.

"7. A process for the recovery of cane sugar, which comprises the elimination of the glucose in'a cane sugar solution by the addition of lime in excess and the application of an approximately boiling-temperature, while the solution is in a non-acid state, removing the excess of lime by carbonic acid, filtering, then boiling the juice obtaining a high purity sugar and a high purity molasses, and finally eflt'ecting a further recovery of sucrose from the molasses by treatment with limeysubstantiall as described.

8. A process 2dr the recovery of cane sugar, which comprises, first, the addition to the cane juice of a quantity of raw sugar, then adding lime to the solution in excess and heating the solution to approximately the boiling point the glucose is thrown down as precipitate, or destroyed, then lime with carbonic acid, and finally filtering the solution; substantially as described.

In testimony whereof I atfix in presence of two witnesses.

EUGENE ERLE BATTELLE Witnesses:

H. B. PENHARLOW, W. LEs'Lm Wnsr;

my signature,

until the greater part of removing the excess of 

